The present application pertains to a low temperature sputter target/backing plate joining technique and to assemblies made thereby.
In my U.S. provisional patent applications No. 60/099,981, filed Sep. 11, 1998 and No. 60/129,559, filed Apr. 16, 1999, a target and backing plate are provided wherein the harder material of the two is machined or otherwise formed so as to have a plurality of ridges or other salient surface portions thereof. These ridges or salient portions are formed along the interior surface of the target or backing plate. The ridged surface is then placed alongside the mating surface of the other member of the assembly along the target/backing plate interface wherein joining will occur.
The peripheral portion of the interfacial surface assembly, surrounding the ridges or salient portions, is joined by conventional means such as electron beam welding, TIG welding, friction welding, soldering, brazing, etc., preferably under vacuum. The assembly is then pressed at a low temperature, preferably at room temperature.
The projections or ridges formed along either the target or backing plate bend upon penetration into the mating metal surface along the target/backing plate interface and form an interlocking grip over the softer metal on the opposing mating surface.
In this invention, a target and backing plate are provided wherein both materials are similar in mechanical properties and both are machined or otherwise formed so as to have a plurality of ridges and grooves or other salient surface portions thereof. These ridges or salient portion are formed along the interior surface of the target or backing plate. The ridged surface is then placed alongside the mating surface (having appropriately positioned mating members) of the other member of the assembly along the target/backing plate interface wherein joining will occur.
The peripheral portion of the interfacial surface assembly is joined by conventional means such as electron beam welding, TIG welding, friction welding, soldering, brazing, etc., preferably under vacuum. The assembly is then pressed at a low temperature, preferably at room temperature.
The projections or ridges formed along either the target or backing plate penetrate into the mating members along the target/backing plate interface. The projections penetrate into the grooves on the opposing mating surface.
The projections and grooves have different sizes so that after penetration, a force or friction fit joint will be formed.